MASS TESTING PROGRAMMES FOR COVID 19 USING NOVEL TESTS
SITUATION
Last week [November 9th] the government proudly announced a major expansion of the UK s testing programme to provide rapid access testing of asymptomatic people for COVID 19 [1].
They claimed this programme was : –
- a“ vital tool to help control this virus and get life back to normal “
- a partnership between national Test and Trace and local public health directors ‘
- to develop the evidence base on how testing with rapid reliable COVID-19 tests can be delivered at scale
Liverpool has nearly completed a two -week “pilot” programme to offer rapid testing to the half a million people who live in the city.
The stated aim of this pilot is to: –
“identify many more cases of COVID and break chains of disease transmission” and
“ to protect those at highest risk from the virus and enable residents to get back to their day to day lives
Meanwhile the Government has also announced following a report by Public Health England / Porton Down [2] that they are extending this pilot and releasing 600000 lateral flow test kits for local authorities to use on asymptomatic people “ at their discretion “.
So far, 87 Local Authorities have opted to take part in this new pilot programme. Each will receive weekly batches of 10000 test kits
ASSESSMENT
The roll out of mass testing on people without symptoms is happening at an alarming pace
SAGE s advice [14] on 10 September 2020 was that: –
“Prioritising rapid testing of symptomatic people is likely to have a greater impact on identifying positive cases and reducing transmission than frequent testing of asymptomatic people in an outbreak area”.
Some highly respected scientists and public health doctors have criticized the conclusions drawn from the evaluation of these novel tests – namely that they are sensitive and specific enough to use on asymptomatic people.
Others have described these mass testing programmes [originally part of Operation Moonshot] to be “scientifically unsound unethical, unevaluated and a costly mess “ [3,4]
What are these concerns?
[Refs 3,4,5,6 7,8]
1 Accuracy of the tests
- The relationship between these novel tests being positive and clinical infectiousness is unknown. [8]
Sensitivity
2 The lateral flow tests chosen for mass testing are not sensitive enough to accurately detect infection when used on asymptomatic people.
Between 1 in 4 and 1 in 2 infectious cases will be missed, when used in the field. Many people will be given false reassurance that they are not infectious and need to have repeat “gold standard” PCR tests to confirm the results.
Specificity
3 When infection rates are low or prevalence is falling as it is in Liverpool , a large number of people will falsely test positive and be told to self isolate. Many will experience the harmful and regressive effects of self-isolation.[ 7 ]
2 Design and evaluation
The National Screening Committee and National Institute for Health Research (NIHR) have not been involved or asked about the design of this programme.
Their design lacks transparency and a clear set of objectives.
No criteria or protocols for evaluation have ever been made available in the public domain.
Unlike other screening programmes, there is no systematic call or recall of an identified, registered population and no expectations about population reach or uptake.
[Initial findings from the Liverpool pilot would appear to indicate that those most at risk of being infected have been the least likely to come forward for testing.
Positivity rates amongst the 110, 000 people tested so far are low [about half that of the current prevalence [ 2.2%] in the north west region [11]
3 Follow up of positive cases and their contacts
More cases will generate many more contacts to follow up
In Liverpool, follow up of positive cases and their contacts has been entrusted to the national Test and Trace system. Over the last 4 months, this national system has only been reaching around 58% of contacts [10] i.e. well below that required to stop onward transmission.
4 Ethical issues
The ethical basis for expanding mass testing using novel tests is very shaky.
These pilot programmes have not undergone the normal process required for ethical approval.
People are invited to have a test which has not yet been properly peer reviewed. The results of these tests if positive could have serious consequences for their personal freedoms, income and well-being. [7]
There are also concerns about the process and practices for gaining consent to participate.
4 Sustainability
The government has, yet again, chosen to use a separate and privately run infrastructure to deliver this mass testing pilot programme.
If rolled out nationally, the Liverpool population mass testing programme would need the equivalent of 260, 000 army personnel to deliver it. It is hugely expensive and not sustainable.
Other options, such as using existing well distributed highly accessible primary care services [including local pharmacies] to provide rapid access testing should have been explored.
5 Overload of local authorities and public health teams
The burden of organizing new testing programmes for asymptomatic people will place another strain on already overburdened local public health teams.
Their priorities should be to: –
- Identify and manage clusters of cases /outbreaks in high risk settings such as schools, care homes, prisons and other geographical hot spot areas [12]
-
Improve adherence to isolation through organizing support and accommodation for people who are finding it difficult to self isolate. [13]
6 Implementation
Implementation has so far been rushed –leading to long queues of both symptomatic and non-symptomatic people, wrong invitation letters issued by schools and questionable practice in relation to “ informed consent”.
The lack of rigour and consistency with respect to research design and implementation across different local authorities means that it will be very difficult understand the impact of these new mass-testing programmes on COVID transmission.
Conclusion
The widespread introduction of these mass screening pilot programmes using novel tests can have serious consequences for people’s lives.
Politicians need to understand that concerns expressed about the choice of tests and the design of these programmes are not just a matter for academic debate or professional discussion.
Accepted standards for design, ethics and evaluation must be adopted – otherwise they could seriously undermine public trust, confidence and future willingness to engage in helping to control this pandemic.
RECOMMENDATIONS
- The continued roll out of these mass screening pilot programmes should be paused immediately.
- 2 The UK National Screening Committee should have oversight of their design and implementation
- Mass screening ‘pilot “programmes should be funded as research – and undertaken through the NIHR in order to ensure public and patient benefit
- Primary care service [including local pharmacies] should be the preferred route for the future distribution of rapid access tests if these are recommended for use by the general population
References
1 https://www.gov.uk/government/news/more-rapid-covid-19-tests-to-be-rolled-out-across-england
3 https://www.bmj.com/content/370/bmj.m3699
Operation Moonshot proposals are scientifically unsound]
Jonathan J Deeks, Anthony J Brookes, Allyson M Pollock
BMJ 2020; 370: m3699 (Published 22 Sep 2020)
4 https://www.bmj.com/content/371/bmj.m4436
5 https://sochealth.co.uk/2020/11/05/asymptomatic-covid-19-screening-in-liverpool/
6 https://blogs.bmj.com/bmj/2020/11/09/screening-the-healthy-population-for-covid-19-is-of-unknown-value-but-is-being-introduced-nationwide/
7 Waugh P. NHS test and trace chief admits workers fear “financial” hit if they self-isolate. Huffington Post 2020 Nov 7.
8
https://journals.sagepub.com/doi/full/10.1177/0141076820967906 –
13 Covid-19: breaking the chain of household transmission. BMJ2020;370:m3181.doi:10.1136/bmj.m3181 pmid:32816710